Not much is known about Keith's backstory. Orphaned at a young age, the only remnants Keith had of his parents was a knife that came from the Blade of Marmora, a Galra resistance group, though he didn't know this at the time. At some point in time, Keith met Shiro, an ace pilot from the Galaxy Garrison, and enrolled in the Garrison himself. During his time as a pilot, Keith was considered one of the best of his generation, which earned jealousy from his classmate Lance. However, disciplinary issues led to Keith being kicked out of the school, and he went to live in a shack in the desert to search for a new purpose in life. That came when Shiro, who was thought to have died while on a mission, crashed on Earth after escaping from an alien empire known as the Galra, which abducted him. After saving him with the help of Lance and two other Garrison students, Hunk and Pidge, the five fled to Keith's shack, and went to find a strange blue mechanical lion that Keith had been having visions of. The Blue Lion then took the five through space, until they reached the planet Arus, where they accidentally freed an alien princess and her adviser from stasis. The princess, Allura, revealed that the lion was a piece of the superweapon Voltron, which the Galra have been searching for, and that there are four other Lions that needed to be found to form Voltron and stop the Galra's conquest of the universe. Keith was chosen to pilot the Red Lion, the most restless and hard to control of the lions.
Skilled Pilot: Keith is an incredible pilot, being considered the best of his generation during his time at the Garrison. He's been able to control a one-man hovercraft that was overweight and still move at high speeds, and maneuver through an asteroid field without getting hit once. This skill got him his position as the Paladin of the Red Lion, and he was even good enough to briefly control the Black Lion, the lion meant for the leader of Voltron to pilot.
Skilled Fighter: Keith is one of the team's best fighters up-close, only behind Shiro. He's been said by Zarkon to fight like a Galra soldier, never giving up unless he wins, or dies trying. However, this determination can send him into a berserker rage during combat, pushing him past his limits, at the cost of clouding his judgement. After awakening his knife and coming to terms with his Galra heritage, Keith learned to adapt his fighting style to incorporate the Blade of Marmora's techniques.
Bond with the Red Lion: Due to Keith's similar personality to the Red Lion, the two have a close bond. This bond is intensified when Keith goes into his berserker rage while in combat, usually resulting in him gaining a new weapon for his lion.
Galra Blood: Due to being a hybrid of human and Galra, Keith is able to interact with and activate Galra technology.
Paladin Armor: The standard armor worn by Paladins of Voltron. The armor protects Keith from harm, allows communication with the other Paladins, and is equipped with a jetpack for sustained flight, along with an energy shield to block attacks. The helmet produces oxygen when worn, allowing Keith to function normally underwater or in a vacuum, and the bracers can fire small lasers or project holograms of Keith.
Bayard: The Bayards are the Paladins' main weapons when on foot. When not in use, they're stored inside the Paladin's armor, and can be summoned to the hand at will. Each Bayard takes the form most suitable for its wielder, and Keith's takes the form of a sword sharp enough to easily slice through steel.
Knife: A knife used by the Blade of Marmora, which is Keith's only remnant of his parents. The blade is made of luxite, making it incredibly sharp, and due to his Galra blood, Keith can will the knife into full-length sword.
The Red Lion: Forged from a meteor that crashed on the Galra homeworld, the Red Lion is one of the five robotic lions that combine together to form Voltron. When the five lions form Voltron, the Red Lion forms into the right arm of the giant robot. The Red Lion is the fastest of the Lions, able to reach Pluto from Earth in seconds and fly fast enough to escape a black hole. It is also incredibly powerful, and can destroy Galra warships with ease.
Armor: The Red Lion's armor is incredibly tough, able to take laser blasts and explosions without a scratch, and withstand heat from a blue star.
Rocket Boosters: All the Lions have rocket boosters located on the back, allowing for high-speed flight. The Lions are each fast enough to travel from Earth to Pluto in seconds, making them faster than the speed of light.
Laser Cannons: The Red Lion has laser cannons stored inside the mouth and tail, both of which have enough power to pierce through a Galra ship in one shot. The mouth laser is for stronger, less accurate shots, while the tail laser is meant for weaker, pinpoint blasts.
Jaw Blade: For close-ranged combat, the Red Lion can form a blade from its jaws that can slice clean through a Galra ship. The jaw blade can also be thrown like a boomerang.
Heat Ray: Due to the Red Lion's elemental affinity for fire, it has a heat ray stored inside its mouth. This ray shoots a stream of scalding magma, which is hot enough to melt the base of a large tower in seconds.
Rail Gun: During Keith's battle with Zarkon, his intense emotions were able to form a large rail gun from the Red Lion's back. Shots from this rail gun are very destructive, able to destroy a large section of Zarkon's space station in one shot.